Concept: This question tests your understanding of plant morphology, specifically identifying different types of stem modifications versus leaf modifications.

Why (C) is correct: The pitcher of Nepenthes (pitcher plant) is a classic example of a leaf modification. The leaf lamina is modified into a pitcher-like structure to trap insects, and the petiole often forms a tendril-like structure for support.

Why other options are wrong:

• (A) Rhizome of ginger: A rhizome is an underground, fleshy, non-green stem modification that grows horizontally.
• (B) Corm of Colocasia: A corm is a condensed, vertical, underground stem modification that stores food.
• (D) Tuber of potato: A tuber is a swollen, underground stem modification that stores food, characterized by 'eyes' which are axillary buds.

Common Mistake: Students often confuse underground stem modifications with root modifications, or leaf modifications with stem modifications due to their unusual appearance.

NEET Tip / Mnemonic: Remember that 'pitcher' is a leaf modification for insectivorous plants, while 'rhizome', 'corm', and 'tuber' are all forms of underground stems.

Correct Answer: (C)